Field of the Disclosure
This invention relates to can taps for use with containers for dispensing materials. More specifically, this invention relates to can taps for dispensing refrigerants from pressurized containers.
Description of the Related Art
Chlorofluorocarbon (CFC), hydrochlorofluorocarbon (HCFC), hydrofluorocarbon (HFC), and hydrofluoroolefin (HFO) compounds have been used extensively as refrigerants, as well as propellants and cleaning solvents. In response to global warming and ozone depletion concerns, new environmental pressures are continuously being exerted on refrigerant service technicians. Refrigeration and air-conditioning (a/c) systems commonly lose refrigerants due to system fatigue, servicing, and/or normal system leakage. Therefore, refrigeration and a/c systems need to be re-charged by adding refrigerant. In the automotive aftermarket, it is very common to recharge a/c systems with small (typically 12 oz. or 1 kg), pressurized refrigerant containers. Small pressurized containers are often used in the mobile aftermarket because of their portability and ability to be taken to the vehicle and re-charge the vehicle, even by do-it-yourself mechanics.
Small aftermarket refrigerant containers are typically provided as single use type containers. These containers normally have a thin metal seal that is destroyed in liberating the refrigerant. A can tap having a needle-shaped pin (which may be referred to as a “piercing tap”) pierces the thin metal seal and allows the contents to be dispensed. An example of such a piercing tap for use with such a can is shown in FIG. 12. Piercing tap 1200 has pin 1220 having needle-shaped tip 1226 that pierces the thin metal seal of a can. An example of a can with a thin metal seal that can be pierced with a piercing tap is shown in FIG. 13.
The cans and can taps presently on the market have several disadvantages. Due to the thin metal seal on the can which must be pierced and ultimately destroyed to dispense the contents, the can cannot be resealed. Therefore, the cans can only be used once before they are discarded. If all of the contents are not used, the excess refrigerant is wasted. Not only does the excess refrigerant represent lost money, but the excess refrigerant is generally released into the atmosphere, which may have environmental implications.
Another issue often encountered with the piercing-type can taps (piercing taps) is inconsistent and/or stopped flow. If the needle-shaped pin is inserted too far into the can, the needle pin will block the flow of the contents out of the can. If the pin is not inserted far enough, the hole in the metal seal may be small and restrict the flow of material out of the can. In typical use, the pin must be inserted and then drawn completely out to achieve optimum flow. However, when technicians actuate the can tap, for example by turning a handle, and begin to remove the pin out of the can, the refrigerant normally starts to flow, so the technician may not fully dis-engage the pin. Finding the best flow or “sweet spot” requires practice to identify when the contents are being properly dispensed.
Cans that are self-sealing (i.e., have a seal that is capable of resealing itself) have recently been introduced in the automotive aftermarket. There are two versions of self-sealing cans. These include external spring-actuated and internal spring-actuated plug type self-sealing cans (which may be referred to as external plug can(s) and internal plug can(s), respectively, singular and plural). The external plug can is well known and there are many taps and/or tap assemblies that are used to liberate product within an external plug can. An example of an external plug can is shown in FIG. 14.
The internal spring-actuated plug type self-sealing can is a newer design. An example of an internal plug can is shown in FIG. 15. At this time, there are no can taps that are specifically designed to work with the new internal plug cans. The seal on these cans have a spring-actuated plug that remains in a sealed position until the plug is depressed. The internal plug can has several advantages over the external plug can. The internal plug design is more robust and may be less prone to damage as the plug portion is contained within can and not external to can. The internal plug can design may also have generally higher flow rate versus the external plug can.
Currently available piercing can taps can be used to release the contents of an internal plug can, but have several drawbacks. First, the needle-shaped pin may damage the plug and/or the seal and may destroy the can's ability to release refrigerant. Second, piercing can taps also provide an inconsistent flow rate similar to the previous can designs. Third, depending on the material of construction of the needle-shaped pin, some pins cannot even sufficiently depress a spring-actuated plug to liberate refrigerant.
It is therefore desirable to develop a system that may overcome one or more of the disadvantages of the currently available products.
It may be desirable to provide a robust can and tap system that is capable of being resealed. Having a robust resealable can and tap system may allow for less material being wasted by allowing the entire contents of the can to be used for the intended purpose. Less waste may also lead to lower costs and less environmental impact.
It may also be desirable to provide a system that is easier to use and/or may yield more consistent results. For example, it may be desirable to provide a system that provides a high and/or consistent flow rate without the need to find the “sweet spot” of the pin.